leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
Log | Files | Refs | README | LICENSE |
commitebb7598f67630b4635caca530d517d57552ef404
parent5104fc73718d42f9e5df45373a78fa4b195e8e28
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateSat, 30 Nov 2024 14:36:47 +0100

Daily Problem

Diffstat:
AProblems/2097.cpp|+++++++++++++++++++++++++++++++++++++++
MREADME.md|+

2 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/Problems/2097.cpp b/Problems/2097.cpp

@@ -0,0 +1,39 @@

class Solution {
public:
vector<vector<int>> validArrangement(const vector<vector<int>> &pairs) const {
unordered_map<int, int> in, out, count;
unordered_map<int, vector<int>> adj;
for (const auto &p : pairs) {
adj[p[0]].push_back(p[1]);
out[p[0]]++, in[p[1]]++;
}
int start = pairs[0][0];
for (const auto &[v, _] : adj) {
if (out[v] - in[v] != 1) continue;
start = v;
break;
}
stack<int> st;
vector<int> res;
for (st.push(start); !st.empty();) {
const int crnt = st.top();
if (count[crnt] != size(adj[crnt])) {
st.push(adj[crnt][count[crnt]++]);
} else {
res.push_back(crnt);
st.pop();
}
}
vector<vector<int>> pair_res;
for (int i = size(res) - 2; i >= 0; i--) {
pair_res.push_back({res[i + 1], res[i]});
}
return pair_res;
}
};

diff --git a/README.md b/README.md

@@ -1192,6 +1192,7 @@ reference and a base for solving problems.

| 2092 | Hard | [Find All People With Secret](Problems/2092.cpp) |
| 2095 | Medium | [Delete the Middle Node of a Linked List](Problems/2095.cpp) |
| 2096 | Medium | [Step-By-Step Directions From a Binary Tree Node to Another](Problems/2096.cpp) |
| 2097 | Hard | [Valid Arrangement of Pairs](Problems/2097.cpp) |
| 2100 | Medium | [Find Good Days to Rob the Bank](Problems/2100.cpp) |
| 2101 | Medium | [Detonate the Maximum Bombs](Problems/2101.cpp) |
| 2104 | Medium | [Sum of Subarray Ranges](Problems/2104.cpp) |